text: /**
   * @author qiao / https://github.com/qiao
   * @author mrdoob / http://mrdoob.com
   * @author alteredq / http://alteredqualia.com/
   * @author WestLangley / http://github.com/WestLangley
   * @author erich666 / http://erichaines.com
   */
  
  // This set of controls performs orbiting, dollying (zooming), and panning.
  // Unlike TrackballControls, it maintains the "up" direction object.up (+Y by default).
  //
  //    Orbit - left mouse / touch: one finger move
  //    Zoom - middle mouse, or mousewheel / touch: two finger spread or squish
  //    Pan - right mouse / touch: three finger swipe
  
  THREE.OrbitControls = function ( object, domElement ) {
  
  	this.object = object;
  
  	this.domElement = ( domElement !== undefined ) ? domElement : document;
  
  	// Set to false to disable this control
  	this.enabled = true;
  
  	// "target" sets the location of focus, where the object orbits around
  	this.target = new THREE.Vector3();
  
  	// How far you can dolly in and out ( PerspectiveCamera only )
  	this.minDistance = 0;
  	this.maxDistance = Infinity;
  
  	// How far you can orbit vertically, upper and lower limits.
  	// Range is 0 to Math.PI radians.
  	this.minPolarAngle = 0; // radians
  	this.maxPolarAngle = Math.PI; // radians
  
  	// How far you can orbit horizontally, upper and lower limits.
  	// If set, must be a sub-interval of the interval [ - Math.PI, Math.PI ].
  	this.minAzimuthAngle = - Infinity; // radians
  	this.maxAzimuthAngle = Infinity; // radians
  
  	// This option actually enables dollying in and out; left as "zoom" for backwards compatibility.
  	// Set to false to disable zooming
  	this.enableZoom = true;
  	this.zoomSpeed = 1.0;
  
  	// Set to false to disable rotating
  	this.enableRotate = true;
  	this.rotateSpeed = 1.0;
  
  	// Set to false to disable panning
  	this.enablePan = true;
  	this.keyPanSpeed = 7.0;	// pixels moved per arrow key push
  
  	// Mouse buttons
  	this.mouseButtons = { ORBIT: THREE.MOUSE.LEFT, ZOOM: THREE.MOUSE.MIDDLE, PAN: THREE.MOUSE.RIGHT };
  
  	// for reset
  	this.target0 = this.target.clone();
  	this.position0 = this.object.position.clone();
  	this.zoom0 = this.object.zoom;
  
  	//
  	// public methods
  	//
  
  	this.getPolarAngle = function () {
  
  		return spherical.phi;
  
  	};
  
  	this.getAzimuthalAngle = function () {
  
  		return spherical.theta;
  
  	};
  
  	this.saveState = function () {
  
  		scope.target0.copy( scope.target );
  		scope.position0.copy( scope.object.position );
  		scope.zoom0 = scope.object.zoom;
  
  	};
  
  	this.reset = function () {
  
  		scope.target.copy( scope.target0 );
  		scope.object.position.copy( scope.position0 );
  		scope.object.zoom = scope.zoom0;
  
  		scope.object.updateProjectionMatrix();
  		scope.dispatchEvent( changeEvent );
  
  		scope.update();
  
  		state = STATE.NONE;
  
  	};
  
  	// this method is exposed, but perhaps it would be better if we can make it private...
  	this.update = function () {
  
  		var offset = new THREE.Vector3();
  
  		// so camera.up is the orbit axis
  		var quat = new THREE.Quaternion().setFromUnitVectors( object.up, new THREE.Vector3( 0, 1, 0 ) );
  		var quatInverse = quat.clone().inverse();
  
  		var lastPosition = new THREE.Vector3();
  		var lastQuaternion = new THREE.Quaternion();
  
  		return function update() {
  
  			var position = scope.object.position;
  
  			offset.copy( position ).sub( scope.target );
  
  			// rotate offset to "y-axis-is-up" space
  			offset.applyQuaternion( quat );
  
  			// angle from z-axis around y-axis
  			spherical.setFromVector3( offset );
  
  			spherical.theta += sphericalDelta.theta;
  			spherical.phi += sphericalDelta.phi;
  
  			// restrict theta to be between desired limits
  			spherical.theta = Math.max( scope.minAzimuthAngle, Math.min( scope.maxAzimuthAngle, spherical.theta ) );
  
  			// restrict phi to be between desired limits
  			spherical.phi = Math.max( scope.minPolarAngle, Math.min( scope.maxPolarAngle, spherical.phi ) );
  
  			spherical.makeSafe();
  
  
  			spherical.radius *= scale;
  
  			// restrict radius to be between desired limits
  			spherical.radius = Math.max( scope.minDistance, Math.min( scope.maxDistance, spherical.radius ) );
  
  			// move target to panned location
  			scope.target.add( panOffset );
  
  			offset.setFromSpherical( spherical );
  
  			// rotate offset back to "camera-up-vector-is-up" space
  			offset.applyQuaternion( quatInverse );
  
  			position.copy( scope.target ).add( offset );
  
  			scope.object.lookAt( scope.target );
  
  			sphericalDelta.set( 0, 0, 0 );
  
  			scale = 1;
  			panOffset.set( 0, 0, 0 );
  
  			// update condition is:
  			// min(camera displacement, camera rotation in radians)^2 > EPS
  			// using small-angle approximation cos(x/2) = 1 - x^2 / 8
  
  			if ( zoomChanged ||
  				lastPosition.distanceToSquared( scope.object.position ) > EPS ||
  				8 * ( 1 - lastQuaternion.dot( scope.object.quaternion ) ) > EPS ) {
  
  				scope.dispatchEvent( changeEvent );
  
  				lastPosition.copy( scope.object.position );
  				lastQuaternion.copy( scope.object.quaternion );
  				zoomChanged = false;
  
  				return true;
  
  			}
  
  			return false;
  
  		};
  
  	}();
  
  	this.dispose = function () {
  
  		scope.domElement.removeEventListener( 'contextmenu', onContextMenu, false );
  		scope.domElement.removeEventListener( 'mousedown', onMouseDown, false );
  		scope.domElement.removeEventListener( 'wheel', onMouseWheel, false );
  
  		scope.domElement.removeEventListener( 'touchstart', onTouchStart, false );
  		scope.domElement.removeEventListener( 'touchend', onTouchEnd, false );
  		scope.domElement.removeEventListener( 'touchmove', onTouchMove, false );
  
  		document.removeEventListener( 'mousemove', onMouseMove, false );
  		document.removeEventListener( 'mouseup', onMouseUp, false );
  
  	};
  
  	//
  	// internals
  	//
  
  	var scope = this;
  
  	var changeEvent = { type: 'change' };
  	var startEvent = { type: 'start' };
  	var endEvent = { type: 'end' };
  
  	var STATE = { NONE: - 1, ROTATE: 0, DOLLY: 1, PAN: 2, TOUCH_ROTATE: 3, TOUCH_DOLLY: 4, TOUCH_PAN: 5 };
  
  	var state = STATE.NONE;
  
  	var EPS = 0.000001;
  
  	// current position in spherical coordinates
  	var spherical = new THREE.Spherical();
  	var sphericalDelta = new THREE.Spherical();
  
  	var scale = 1;
  	var panOffset = new THREE.Vector3();
  	var zoomChanged = false;
  
  	var rotateStart = new THREE.Vector2();
  	var rotateEnd = new THREE.Vector2();
  	var rotateDelta = new THREE.Vector2();
  
  	var panStart = new THREE.Vector2();
  	var panEnd = new THREE.Vector2();
  	var panDelta = new THREE.Vector2();
  
  	var dollyStart = new THREE.Vector2();
  	var dollyEnd = new THREE.Vector2();
  	var dollyDelta = new THREE.Vector2();
  
  	function getZoomScale() {
  
  		return Math.pow( 0.95, scope.zoomSpeed );
  
  	}
  
  	function rotateLeft( angle ) {
  
  		sphericalDelta.theta -= angle;
  
  	}
  
  	function rotateUp( angle ) {
  
  		sphericalDelta.phi -= angle;
  
  	}
  
  	var panLeft = function () {
  
  		var v = new THREE.Vector3();
  
  		return function panLeft( distance, objectMatrix ) {
  
  			v.setFromMatrixColumn( objectMatrix, 0 ); // get X column of objectMatrix
  			v.multiplyScalar( - distance );
  
  			panOffset.add( v );
  
  		};
  
  	}();
  
  	var panUp = function () {
  
  		var v = new THREE.Vector3();
  
  		return function panUp( distance, objectMatrix ) {
  
  			v.setFromMatrixColumn( objectMatrix, 1 ); // get Y column of objectMatrix
  			v.multiplyScalar( distance );
  
  			panOffset.add( v );
  
  		};
  
  	}();
  
  	// deltaX and deltaY are in pixels; right and down are positive
  	var pan = function () {
  
  		var offset = new THREE.Vector3();
  
  		return function pan( deltaX, deltaY ) {
  
  			var element = scope.domElement === document ? scope.domElement.body : scope.domElement;
  
  			if ( scope.object.isPerspectiveCamera ) {
  
  				// perspective
  				var position = scope.object.position;
  				offset.copy( position ).sub( scope.target );
  				var targetDistance = offset.length();
  
  				// half of the fov is center to top of screen
  				targetDistance *= Math.tan( ( scope.object.fov / 2 ) * Math.PI / 180.0 );
  
  				// we actually don't use screenWidth, since perspective camera is fixed to screen height
  				panLeft( 2 * deltaX * targetDistance / element.clientHeight, scope.object.matrix );
  				panUp( 2 * deltaY * targetDistance / element.clientHeight, scope.object.matrix );
  
  			} else {
  
  				// camera neither orthographic nor perspective
  				console.warn( 'WARNING: OrbitControls.js encountered an unknown camera type - pan disabled.' );
  				scope.enablePan = false;
  
  			}
  
  		};
  
  	}();
  
  	function dollyIn( dollyScale ) {
  
  		if ( scope.object.isPerspectiveCamera ) {
  
  			scale /= dollyScale;
  
  		} else {
  
  			console.warn( 'WARNING: OrbitControls.js encountered an unknown camera type - dolly/zoom disabled.' );
  			scope.enableZoom = false;
  
  		}
  
  	}
  
  	function dollyOut( dollyScale ) {
  
  		if ( scope.object.isPerspectiveCamera ) {
  
  			scale *= dollyScale;
  
  		} else {
  
  			console.warn( 'WARNING: OrbitControls.js encountered an unknown camera type - dolly/zoom disabled.' );
  			scope.enableZoom = false;
  
  		}
  
  	}
  
  	//
  	// event callbacks - update the object state
  	//
  
  	function handleMouseDownRotate( event ) {
  
  		//console.log( 'handleMouseDownRotate' );
  
  		rotateStart.set( event.clientX, event.clientY );
  
  	}
  
  	function handleMouseDownDolly( event ) {
  
  		//console.log( 'handleMouseDownDolly' );
  
  		dollyStart.set( event.clientX, event.clientY );
  
  	}
  
  	function handleMouseDownPan( event ) {
  
  		//console.log( 'handleMouseDownPan' );
  
  		panStart.set( event.clientX, event.clientY );
  
  	}
  
  	function handleMouseMoveRotate( event ) {
  
  		//console.log( 'handleMouseMoveRotate' );
  
  		rotateEnd.set( event.clientX, event.clientY );
  		rotateDelta.subVectors( rotateEnd, rotateStart );
  
  		var element = scope.domElement === document ? scope.domElement.body : scope.domElement;
  
  		// rotating across whole screen goes 360 degrees around
  		rotateLeft( 2 * Math.PI * rotateDelta.x / element.clientWidth * scope.rotateSpeed );
  
  		// rotating up and down along whole screen attempts to go 360, but limited to 180
  		rotateUp( 2 * Math.PI * rotateDelta.y / element.clientHeight * scope.rotateSpeed );
  
  		rotateStart.copy( rotateEnd );
  
  		scope.update();
  
  	}
  
  	function handleMouseMoveDolly( event ) {
  
  		//console.log( 'handleMouseMoveDolly' );
  
  		dollyEnd.set( event.clientX, event.clientY );
  
  		dollyDelta.subVectors( dollyEnd, dollyStart );
  
  		if ( dollyDelta.y > 0 ) {
  
  			dollyIn( getZoomScale() );
  
  		} else if ( dollyDelta.y < 0 ) {
  
  			dollyOut( getZoomScale() );
  
  		}
  
  		dollyStart.copy( dollyEnd );
  
  		scope.update();
  
  	}
  
  	function handleMouseMovePan( event ) {
  
  		//console.log( 'handleMouseMovePan' );
  
  		panEnd.set( event.clientX, event.clientY );
  
  		panDelta.subVectors( panEnd, panStart );
  
  		pan( panDelta.x, panDelta.y );
  
  		panStart.copy( panEnd );
  
  		scope.update();
  
  	}
  
  	function handleMouseUp( event ) {
  
  		// console.log( 'handleMouseUp' );
  
  	}
  
  	function handleMouseWheel( event ) {
  
  		// console.log( 'handleMouseWheel' );
  
  		if ( event.deltaY < 0 ) {
  
  			dollyOut( getZoomScale() );
  
  		} else if ( event.deltaY > 0 ) {
  
  			dollyIn( getZoomScale() );
  
  		}
  
  		scope.update();
  
  	}
  
  	function handleTouchStartRotate( event ) {
  
  		//console.log( 'handleTouchStartRotate' );
  
  		rotateStart.set( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY );
  
  	}
  
  	function handleTouchStartDolly( event ) {
  
  		//console.log( 'handleTouchStartDolly' );
  
  		var dx = event.touches[ 0 ].pageX - event.touches[ 1 ].pageX;
  		var dy = event.touches[ 0 ].pageY - event.touches[ 1 ].pageY;
  
  		var distance = Math.sqrt( dx * dx + dy * dy );
  
  		dollyStart.set( 0, distance );
  
  	}
  
  	function handleTouchStartPan( event ) {
  
  		//console.log( 'handleTouchStartPan' );
  
  		panStart.set( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY );
  
  	}
  
  	function handleTouchMoveRotate( event ) {
  
  		//console.log( 'handleTouchMoveRotate' );
  
  		rotateEnd.set( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY );
  		rotateDelta.subVectors( rotateEnd, rotateStart );
  
  		var element = scope.domElement === document ? scope.domElement.body : scope.domElement;
  
  		// rotating across whole screen goes 360 degrees around
  		rotateLeft( 2 * Math.PI * rotateDelta.x / element.clientWidth * scope.rotateSpeed );
  
  		// rotating up and down along whole screen attempts to go 360, but limited to 180
  		rotateUp( 2 * Math.PI * rotateDelta.y / element.clientHeight * scope.rotateSpeed );
  
  		rotateStart.copy( rotateEnd );
  
  		scope.update();
  
  	}
  
  	function handleTouchMoveDolly( event ) {
  
  		//console.log( 'handleTouchMoveDolly' );
  
  		var dx = event.touches[ 0 ].pageX - event.touches[ 1 ].pageX;
  		var dy = event.touches[ 0 ].pageY - event.touches[ 1 ].pageY;
  
  		var distance = Math.sqrt( dx * dx + dy * dy );
  
  		dollyEnd.set( 0, distance );
  
  		dollyDelta.subVectors( dollyEnd, dollyStart );
  
  		if ( dollyDelta.y > 0 ) {
  
  			dollyOut( getZoomScale() );
  
  		} else if ( dollyDelta.y < 0 ) {
  
  			dollyIn( getZoomScale() );
  
  		}
  
  		dollyStart.copy( dollyEnd );
  
  		scope.update();
  
  	}
  
  	function handleTouchMovePan( event ) {
  
  		//console.log( 'handleTouchMovePan' );
  
  		panEnd.set( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY );
  
  		panDelta.subVectors( panEnd, panStart );
  
  		pan( panDelta.x, panDelta.y );
  
  		panStart.copy( panEnd );
  
  		scope.update();
  
  	}
  
  	function handleTouchEnd( event ) {
  
  		//console.log( 'handleTouchEnd' );
  
  	}
  
  	//
  	// event handlers - FSM: listen for events and reset state
  	//
  
  	function onMouseDown( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		event.preventDefault();
  
  		switch ( event.button ) {
  
  			case scope.mouseButtons.ORBIT:
  
  				if ( scope.enableRotate === false ) return;
  
  				handleMouseDownRotate( event );
  
  				state = STATE.ROTATE;
  
  				break;
  
  			case scope.mouseButtons.ZOOM:
  
  				if ( scope.enableZoom === false ) return;
  
  				handleMouseDownDolly( event );
  
  				state = STATE.DOLLY;
  
  				break;
  
  			case scope.mouseButtons.PAN:
  
  				if ( scope.enablePan === false ) return;
  
  				handleMouseDownPan( event );
  
  				state = STATE.PAN;
  
  				break;
  
  		}
  
  		if ( state !== STATE.NONE ) {
  
  			document.addEventListener( 'mousemove', onMouseMove, false );
  			document.addEventListener( 'mouseup', onMouseUp, false );
  
  			scope.dispatchEvent( startEvent );
  
  		}
  
  	}
  
  	function onMouseMove( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		event.preventDefault();
  
  		switch ( state ) {
  
  			case STATE.ROTATE:
  
  				if ( scope.enableRotate === false ) return;
  
  				handleMouseMoveRotate( event );
  
  				break;
  
  			case STATE.DOLLY:
  
  				if ( scope.enableZoom === false ) return;
  
  				handleMouseMoveDolly( event );
  
  				break;
  
  			case STATE.PAN:
  
  				if ( scope.enablePan === false ) return;
  
  				handleMouseMovePan( event );
  
  				break;
  
  		}
  
  	}
  
  	function onMouseUp( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		handleMouseUp( event );
  
  		document.removeEventListener( 'mousemove', onMouseMove, false );
  		document.removeEventListener( 'mouseup', onMouseUp, false );
  
  		scope.dispatchEvent( endEvent );
  
  		state = STATE.NONE;
  
  	}
  
  	function onMouseWheel( event ) {
  
  		if ( scope.enabled === false || scope.enableZoom === false || ( state !== STATE.NONE && state !== STATE.ROTATE ) ) return;
  
  		event.preventDefault();
  		event.stopPropagation();
  
  		handleMouseWheel( event );
  
  		scope.dispatchEvent( startEvent ); // not sure why these are here...
  		scope.dispatchEvent( endEvent );
  
  	}
  
  	function onTouchStart( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		switch ( event.touches.length ) {
  
  			case 1:	// one-fingered touch: rotate
  
  				if ( scope.enableRotate === false ) return;
  
  				handleTouchStartRotate( event );
  
  				state = STATE.TOUCH_ROTATE;
  
  				break;
  
  			case 2:	// two-fingered touch: dolly
  
  				if ( scope.enableZoom === false ) return;
  
  				handleTouchStartDolly( event );
  
  				state = STATE.TOUCH_DOLLY;
  
  				break;
  
  			case 3: // three-fingered touch: pan
  
  				if ( scope.enablePan === false ) return;
  
  				handleTouchStartPan( event );
  
  				state = STATE.TOUCH_PAN;
  
  				break;
  
  			default:
  
  				state = STATE.NONE;
  
  		}
  
  		if ( state !== STATE.NONE ) {
  
  			scope.dispatchEvent( startEvent );
  
  		}
  
  	}
  
  	function onTouchMove( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		event.preventDefault();
  		event.stopPropagation();
  
  		switch ( event.touches.length ) {
  
  			case 1: // one-fingered touch: rotate
  
  				if ( scope.enableRotate === false ) return;
  				if ( state !== STATE.TOUCH_ROTATE ) return; // is this needed?...
  
  				handleTouchMoveRotate( event );
  
  				break;
  
  			case 2: // two-fingered touch: dolly
  
  				if ( scope.enableZoom === false ) return;
  				if ( state !== STATE.TOUCH_DOLLY ) return; // is this needed?...
  
  				handleTouchMoveDolly( event );
  
  				break;
  
  			case 3: // three-fingered touch: pan
  
  				if ( scope.enablePan === false ) return;
  				if ( state !== STATE.TOUCH_PAN ) return; // is this needed?...
  
  				handleTouchMovePan( event );
  
  				break;
  
  			default:
  
  				state = STATE.NONE;
  
  		}
  
  	}
  
  	function onTouchEnd( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		handleTouchEnd( event );
  
  		scope.dispatchEvent( endEvent );
  
  		state = STATE.NONE;
  
  	}
  
  	function onContextMenu( event ) {
  
  		if ( scope.enabled === false ) return;
  
  		event.preventDefault();
  
  	}
  
  	//
  
  	scope.domElement.addEventListener( 'contextmenu', onContextMenu, false );
  
  	scope.domElement.addEventListener( 'mousedown', onMouseDown, false );
  	scope.domElement.addEventListener( 'wheel', onMouseWheel, false );
  
  	scope.domElement.addEventListener( 'touchstart', onTouchStart, false );
  	scope.domElement.addEventListener( 'touchend', onTouchEnd, false );
  	scope.domElement.addEventListener( 'touchmove', onTouchMove, false );
  
  	// force an update at start
  
  	this.update();
  
  };
  
  THREE.OrbitControls.prototype = Object.create( THREE.EventDispatcher.prototype );
  THREE.OrbitControls.prototype.constructor = THREE.OrbitControls;
  